Sound amplifier



FIG. 1 is a perspective view from the top, front and right side of a sound amplifier showing my new design;

FIG. 2 is a perspective view from the top, rear and left side thereof;

FIG. 3 is a frontal elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof; and,

FIG. 7 is a top plan view thereof. 

The ornamental design for a sound amplifier, as shown and described. 